JP2020047233A - Traffic signal control system, traffic signal control method, traffic signal control machine, and computer program - Google Patents

Abstract

To provide a traffic signal control system which can appropriately perform signal control.SOLUTION: A traffic signal control system comprises: a plurality of traffic signal control machines; and a central device which notifies the plurality of traffic signal control machines of signal control commands, in which the central device has: an upper side control part which generates the signal control commands for every plurality of traffic signal control machines; and an upper side communication part which transmits the generated signal control commands to the plurality of traffic signal control machines, respectively, the plurality of traffic signal control machines have: lower side communication parts which receive the signal control command of an own machine; lower side control part which control a signal light device based on the received signal control commands; and lower side storage parts which store lower side accumulation data which is a data group of accumulating the received signal control commands of the own machine, and the lower side control parts control the signal light device based on the signal control command corresponding to a present date type and time among the signal control commands of the own machine included in the lower side accumulation data when poor communication is generated between it and the central device.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a traffic signal control system, a traffic signal control method, a traffic signal controller, and a computer program.

The traffic signal control system includes a centralized control system (remote control) in which the operation of traffic signal controllers at each intersection is controlled collectively by the central unit of the traffic control center, and a point control system in which each traffic signal controller operates independently. (See Non-Patent Document 1).
In the centralized control method, centralized control is performed by connecting a central device and a traffic signal controller via a communication line or the like and transmitting a signal control command from the central device to the traffic signal controller.

"Revised Guide to Traffic Signals", Japan Society for Traffic Engineering, July 2006, p. 96-98

  The central device in the centralized control system may perform system control on the route by centrally controlling a plurality of traffic signal controllers installed at a plurality of intersections included in a certain section.

  As a communication line connecting the central device and the traffic signal controller, a wired telephone line or the like is generally used. For example, a terminal device of a mobile communication system such as LTE (Long Term Evolution) is used for the central device and the traffic signal controller. It is also conceivable to carry out wireless communication between the central device and the traffic signal controller and transmit a signal control command.

  In this case, when a communication failure such as a communication break occurs due to a change in a radio wave propagation path or the like between any one of the plurality of traffic signal controllers and the central device, the central device performs communication. There is a possibility that appropriate signal control cannot be performed, for example, a signal control command cannot be given to the traffic signal controller in which the failure has occurred, and system control cannot be maintained.

  The present invention has been made in view of such circumstances, and has as its object to provide a technique capable of appropriately performing signal control.

  The traffic signal control system according to an embodiment includes a plurality of traffic signal controllers installed at intersections included in a system control section, and a signal control command for system control notified to the plurality of traffic signal controllers. A central device, which comprises: a higher-level control unit that generates the signal control command for each of the plurality of traffic signal controllers; and the generated signal control command. An upper communication unit for transmitting to each of the plurality of traffic signal controllers, wherein the plurality of traffic signal controllers include a lower communication unit for receiving the signal control command of the own device, and the received signal control A lower-side control unit that controls the signal lamp based on the command, and a lower-side storage unit that stores lower-side accumulated data, which is a data group in which the received signal control command of the own device is stored, Above said The side control unit, when a communication failure occurs with the central device, among the signal control commands of the own device included in the lower-order accumulated data, a signal control command corresponding to a current day type and time. The signal light is controlled based on the following.

  Also, a traffic signal control method according to another embodiment includes a plurality of traffic signal controllers installed at intersections included in a system control section, and a plurality of traffic signal control commands for system control. A traffic signal control method performed by the central device, wherein the central device generates the signal control command for each of the plurality of traffic signal controllers, and the central device generates the traffic control command. Transmitting the signal control command to each of the plurality of traffic signal controllers, the traffic signal controller receiving the signal control command of the own device, and the traffic signal controller receiving the signal. Controlling the signal light based on the control command, and the traffic signal controller stores the lower-order stored data, which is a data group in which the received signal control command of the own device is stored. Remembering, wherein the traffic signal controller controls the signal light based on the received signal control command, when the communication failure with the central device occurs, the lower traffic signal controller. The signal lamp is controlled based on the signal control command corresponding to the current day type and time among the signal control commands of the own device included in the side accumulated data.

  A traffic signal controller according to another embodiment is a traffic signal controller installed at an intersection included in a system control section, and includes a lower communication unit that receives a signal control command for system control, A lower-side control unit that controls the signal lamp based on the signal control command, and a lower-side storage unit that stores lower-side accumulated data, which is a data group in which the received signal control command is stored. The lower control unit, when a communication failure occurs with the central device that notifies the signal control command, the signal control command included in the lower storage data, the current day type and time The signal lamp is controlled based on a signal control command corresponding to

  A computer program according to still another embodiment is a computer program for causing a computer to execute control of a signal light by a traffic signal controller installed at an intersection included in a section of system control. Receiving the signal control command for, and controlling the signal lamp based on the received signal control command, and a lower-order stored data, which is a data group in which the received signal control command is stored. Storing, and a computer program for executing, wherein the step of controlling the signal light device based on the received signal control command, when a communication failure occurs with a central device that notifies the signal control command Among the signal control commands included in the lower accumulation data, the current day type and time A computer program for controlling the signal lamp device on the basis of a signal control command to respond.

  According to the present invention, a signal control finger can be appropriately performed.

FIG. 1 is a diagram illustrating an example of the overall configuration of a traffic signal control system. FIG. 2 is a block diagram illustrating an example of a configuration of the traffic signal controller. FIG. 3 is a functional block diagram showing the internal configuration of the central device. FIG. 4 is a flowchart illustrating an example of a signal lamp control process performed by the control unit of the traffic signal controller according to the first embodiment. FIG. 5 is a diagram illustrating an example of a signal control command transmitted from the central device. FIG. 6 is a diagram illustrating an example of the receiving-side database stored in the storage unit of the traffic signal controller. FIG. 7 is a flowchart illustrating an example of the normal processing. FIG. 8 is a flowchart illustrating an example of the non-receiving process. FIG. 9 is a flowchart illustrating an example of a signal control command transmission process performed by the control unit of the central device. FIG. 10 is a flowchart illustrating an example of the maintenance process. FIG. 11 is a diagram illustrating an example of the transmission-side database stored in the storage unit of the central device. FIG. 12 is a diagram for explaining the operation of each traffic signal controller and the central device when the communication of one traffic signal controller is disconnected in the system of the first embodiment. FIG. 13 is a sequence diagram illustrating an example of the restoration process. FIG. 14 is a diagram illustrating an example of signal control execution information transmitted by the traffic signal controller. FIG. 15 is a diagram illustrating an example of loss compensation information transmitted by the traffic signal controller. FIG. 16 is a flowchart illustrating an example of a maintenance process performed by the central device of the system according to the second embodiment. FIG. 17 is a diagram for explaining operations of each traffic signal controller and the central device when communication of one traffic signal controller is disconnected in the system of the second embodiment. FIG. 18 is a diagram for explaining another example when specifying an execution target.

First, the contents of the embodiment will be listed and described.
[Overview of Embodiment]
(1) A traffic signal control system according to an embodiment includes a plurality of traffic signal controllers installed at intersections included in a system control section, and a plurality of traffic signal control commands for system control. And a central device for notifying the traffic signal control device, wherein the central device generates the signal control command for each of the plurality of traffic signal controllers, an upper control unit, and the generated signal control. An upper communication unit that transmits a command to each of the plurality of traffic signal controllers, and the plurality of traffic signal controllers receive a lower communication unit that receives the signal control command of the own device; A lower control unit that controls the signal lamp based on the signal control command, and a lower storage unit that stores lower stored data, which is a data group in which the received signal control command of the own device is stored. Have The lower control unit, when a communication failure occurs with the central device, among the signal control commands of the own device included in the lower storage data, a signal corresponding to the current day type and time. The signal lamp is controlled based on a control command.

  According to the system having the above configuration, even if a traffic signal controller in which a communication failure such as communication disconnection has occurred is included in the plurality of traffic signal controllers, the traffic signal controller in which the communication failure occurs has a lower rank. Since the signal lamp is controlled based on the signal control command corresponding to the current time in the side accumulated data, the signal control executed in the past is executed with the same day type and time as the present. Thus, the control executed in the past traffic situation similar to the current traffic situation can be executed, and the signal control can be appropriately performed.

(2) In the traffic signal control system, the central device stores a higher-order accumulated data, which is a data group in which the transmitted signal control command is accumulated for each of the plurality of traffic signal controllers. It is preferable to further have

(3) In the above traffic signal control system, when the upper-level control unit detects the following disconnection controller, the upper-level control unit outputs the current signal control command of the disconnection controller included in the upper-level accumulated data. It is preferable to extract a signal control command of the cutting controller corresponding to the day type and time, and to generate the signal control command of the following peripheral controller based on the extracted signal control command of the cutting controller. .
Disconnect controller: Traffic signal controller with communication failure with central unit Peripheral controller: Traffic signal controller included in the same system control section as disconnect controller and communicating with central unit The side controller can obtain a signal control command currently used by the cutting controller. Furthermore, since the signal control command of the peripheral controller is generated based on the signal control command currently used by the cutting controller, the signal control of the peripheral controller is more appropriately performed in accordance with the signal control of the cutting controller. be able to. As a result, system control between the cutting controller and the peripheral controller can be more appropriately maintained.

(4) In the above traffic signal control system, it is preferable that, when detecting the following disconnection controller, the upper control unit stops transmitting the signal control command to the following peripheral controller.
Disconnect controller: a traffic signal controller in which communication failure has occurred with the central device. Peripheral controller: a traffic signal controller included in the same system control section as the disconnect controller and communicating with the central device. When the transmission of the signal control command is stopped, the controller determines that a communication failure has occurred, similarly to the disconnection controller, and executes the signal control based on the signal control command corresponding to the current day type and time. I do. As a result, the signal control executed in the past at the same day type and time as the present at a plurality of intersections can be reproduced, and the system control can be maintained.

(5) In the traffic signal control system, it is preferable that each intersection where the disconnection control device and the peripheral control device are installed forms one sub-area in the section.
In this case, appropriate signal control can be performed in a traffic signal controller that performs signal control with the same cycle length.

(6) In the traffic signal control system, it is preferable that each intersection where the peripheral controller is installed is located in a predetermined range in the section based on an intersection where the cutting controller is installed.

(7) In the traffic signal control system, it is preferable that the predetermined range is a range from an intersection where the cutting control device is installed to an intersection located before an important intersection adjacent to the intersection.

(8) In the above traffic signal control system, the plurality of traffic signal controllers generate execution information indicating the control of the signal lamps executed by the traffic lights and accumulate the execution information in the lower storage unit. The central device transmits a transmission request for requesting transmission of execution information generated during a predetermined period of the execution information stored in the lower storage unit to at least one traffic signal of the plurality of traffic signal controllers. It is preferable that the traffic information is transmitted to a controller and the execution information for the predetermined period is transmitted to the one traffic signal controller.
In this case, the central device can acquire the execution information of the traffic signal controller during the communication failure as the execution history.

(9) In a traffic signal control method according to another embodiment, a plurality of traffic signal controllers installed at intersections included in a system control section and a signal control command for system control are transmitted to the plurality of traffic signal controllers. A central device for notifying a controller, a traffic signal control method performed by the central device, wherein the central device generates the signal control command for each of the plurality of traffic signal controllers; Transmitting the signal control command to each of the plurality of traffic signal controllers, the traffic signal controller receiving the signal control command of the own device, and the traffic signal controller receiving the signal control command. Controlling the signal lamp based on the signal control command, and the traffic signal controller reads the lower-order stored data, which is a data group in which the received signal control command of the own device is stored. Remembering, wherein the traffic signal controller controls the signal light based on the received signal control command, when the communication failure with the central device occurs, the lower traffic signal controller. The signal lamp is controlled based on the signal control command corresponding to the current day type and time among the signal control commands of the own device included in the side accumulated data.

(10) A traffic signal controller according to another embodiment is a traffic signal controller installed at an intersection included in a section for system control, and is a lower communication system that receives a signal control command for system control. Unit, a lower control unit that controls the signal lamp based on the received signal control command, and a lower storage unit that stores lower storage data, which is a data group that stores the received signal control command. The, the lower control unit, when a communication failure occurs with the central device that notifies the signal control command, among the signal control commands included in the lower storage data, The signal lamp is controlled based on a signal control command corresponding to a day type and a time.

(11) A computer program according to another embodiment is a computer program for causing a computer to execute control of a signal light by a traffic signal controller installed at an intersection included in a section of system control. A step of receiving a signal control command for system control, a step of controlling the signal lamp based on the received signal control command, and a data group in which the received signal control command is stored. Storing the data, and controlling the signal lamp based on the received signal control command, wherein a communication failure occurs with a central device that notifies the signal control command. In this case, among the signal control commands included in the lower accumulation data, the current day type and time A computer program for controlling the signal lamp device on the basis of the corresponding signal control command.

[Details of Embodiment]
Hereinafter, preferred embodiments will be described with reference to the drawings.
In addition, at least a part of each embodiment described below may be arbitrarily combined.

[Overall configuration of traffic signal control system]
FIG. 1 is a diagram illustrating an example of the overall configuration of a traffic signal control system.
1, a traffic signal control system 1 includes a plurality of signal lights 2, a plurality of traffic signal controllers 4, a central device 6, a roadside sensor 8, a roadside communication device 10, and the like.

In FIG. 1, the signal light 2 and the traffic signal controller 4 are installed at each of a plurality of intersections Ci (i = 1 to 12).
In FIG. 1, only one signal light device 2 is shown at each intersection Ci for simplicity of illustration, but actually four signal light devices 2 are installed for ascending and descending roads that cross each other. You.

The central device 6 is installed in a traffic control center or the like.
The traffic signal controller 4 and the central device 6 can perform wireless communication using a mobile communication system such as LTE (Long Term Evolution), and can mutually exchange information by performing wireless communication with each other.

The central device 6 controls the traffic signal controllers 4 belonging to the area under the jurisdiction of the own device 6 by controlling the traffic signal controllers 4 on the same section. Has the function of executing
The central device 6 generates a signal control parameter based on traffic information obtained from the roadside sensor 8 and the roadside communication device 10 and transmits a signal control command including the signal control parameter to each traffic signal control device 4.

  The traffic signal controller 4 receives a signal control command given from the central device 6 via wireless communication, and performs lighting control (signal control) of the signal lamp 2 based on the signal control command.

The roadside sensor 8 measures, for example, a vehicle detector that ultrasonically senses the vehicle 5 running immediately below, a loop coil that senses the vehicle 5 based on a change in inductance, or image processing of a camera image to measure traffic volume and vehicle speed. And an image sensor.
The roadside sensor 8 is installed on the upstream side of each road extending from the target intersection Ci, and measures the number of vehicles (inflow traffic volume) flowing into the intersection Ci and the vehicle speed.

The roadside sensor 8 is connected to the traffic signal controller 4 installed at the target intersection Ci via a wired or wireless communication line. The roadside sensor 8 gives the measurement result to the traffic signal controller 4 through a communication line. The measurement result is used by the traffic signal controller 4 for controlling the color of the signal light 2, and is transferred to the central device 6 by the traffic signal controller 4.
The measurement results include the traffic volume flowing into the intersection Ci, the measurement results of the vehicle speed, and the like.

The roadside communication device 10 is a wireless communication device that wirelessly transmits and receives various information to and from a vehicle-mounted communication device mounted on the vehicle 5.
The roadside communication device 10 has a wireless communication function using a wireless LAN, an optical beacon, a radio wave beacon, or the like. The roadside communication device 10 is installed on the upstream side of each road extending from the target intersection Ci, and can communicate with the vehicle-mounted communication device of the vehicle 5 traveling on the upstream side of the road flowing into the target intersection Ci.

  The roadside communication device 10 is connected to the traffic signal control device 4 installed at the target intersection Ci via a wired or wireless communication line. The roadside communication device 10 can exchange information with the central device 6 via the traffic signal controller 4 connected by a communication line.

The roadside communication device 10 transmits traffic information and the like distributed by the central device 6 to the onboard communication device. In addition, the roadside communication device 10 receives probe information and the like of the vehicle 5 from the onboard communication device and transmits the information to the central device 6 via the traffic signal controller 4.
The probe information of the vehicle 5 includes vehicle information such as position information, speed information, vehicle type information, and vehicle ID of the vehicle 5.

FIG. 2 is a block diagram illustrating an example of the configuration of the traffic signal controller 4.
The traffic signal controller 4 controls lighting, extinguishing, and blinking of each of the signal lights such as blue, yellow, and red of the signal light 2 based on a signal control command from the central device 6.
As shown in FIG. 2, the traffic signal controller 4 includes a control unit 14 (lower-side control unit), a lamp driving unit 16, a communication unit 18 (lower-side communication unit), and a storage unit 20 (lower-side storage unit). Part).

The control unit 14 includes a CPU (Central Processing Unit) and the like, and configures a computer together with the storage unit 20 including a memory and a hard disk.
The storage unit 20 stores various computer programs and data to be executed by the control unit 14. The functions of the control unit 14 are realized by the control unit 14 executing these computer programs.

The lamp driving unit 16 includes a semiconductor relay (not shown), and turns on / off the power supplied to each signal lamp of the signal lamp 2 based on the signal switching timing generated by the control unit 14.
The communication unit 18 has a function as a terminal device of the mobile communication system, and performs wireless communication with the central device 6.

The control unit 14 is connected to the lamp driving unit 16 and the communication unit 18 via an internal bus. The control unit 14 controls the operation of each of these hardware units.
The control unit 14 generates a lamp color switching timing of the signal lamp 2 according to a signal control command given by wireless communication from the central device 6. Further, when terminal control is permitted by the central device 6, the control unit 14 generates the lamp color switching timing of the signal lamp 2 according to the result of the terminal response control performed by the control device 14 itself.
The traffic signal controller 4 controls the signal lamp 2 by generating a lamp color switching timing based on a signal control command or the like and driving the signal lamp 2 based on the timing.

In addition, the control unit 14 has a function of registering the received signal control command in a reception-side database 42 (described later) stored in the storage unit 20.
Further, when a communication failure occurs with the central device 6, the control unit 14 controls the signal lamp 2 based on a signal control command corresponding to the current day type and time from the reception side database 42. Has a function.

Further, the control unit 14 generates signal control execution information indicating the content of the signal control executed by the own device 4, registers the signal control execution information in an execution information database 49 (described later) stored in the storage unit 20, and It also has a function of transmitting control execution information to the central device 6.
In addition, the control unit 14 has a function of transferring the measurement result given from the roadside sensor 8 and the probe information given from the roadside communication device 10 to the central device 6. The control unit 14 also has a function of transferring traffic information for the on-board communication device provided from the central device 6 to the roadside communication device 10.

  In addition, when registering the signal control command from the central device 6 in the receiving side database 42 stored in the storage unit 20, the control unit 14 partially stores the stairs (to stop at a specific step) described later. A function may be provided for selecting and setting not to register for the item. The control unit 14 may have a function of not registering the signal control command in the receiving-side database 42 stored in the storage unit 20 when receiving the notification from the central device 6 that the signal control command is not registered.

The storage unit 20 stores the above-described receiving database 42 and the execution information database 49 in addition to various computer programs.
The receiving-side database 42 is a database for storing received signal control commands of the own device 4 and stores a plurality of received signal control commands. That is, the receiving side database 42 constitutes lower side accumulated data which is a data group in which the received signal control commands are accumulated.
The execution information database 49 is a database for storing the signal control execution information generated by the control unit 14, and stores a plurality of signal control execution information generated by the control unit 14 in the past.

FIG. 3 is a functional block diagram showing the internal configuration of the central device 6.
As shown in FIG. 3, the central device 6 of the present embodiment includes a control unit 22 (upper control unit), a display unit 24, a communication unit 26 (upper communication unit), and a storage unit 28 (upper storage unit). ) And an operation unit 30.

The control unit 22 is configured by a CPU and the like, and configures a computer together with the storage unit 28 including a memory and a hard disk.
The storage unit 28 stores various computer programs and data to be executed by the control unit 22. The functions of the control unit 22 are realized by the control unit 22 executing these computer programs.

  The communication unit 26 has a function as a terminal device of the mobile communication system, and performs wireless communication with each traffic signal controller 4.

The control unit 22 is connected to the above-mentioned hardware units via an internal bus, and controls the operations of these units.
The control unit 22 collects the measurement result of the roadside sensor 8 and the probe information from the roadside communication device 10 and processes various traffic information, and also supplies a signal to each traffic signal controller 4 based on the traffic information and the like. A control command is generated for each traffic signal controller 4.

The control unit 22 gives a signal control command generated for each traffic signal controller 4 to each traffic signal controller 4, and performs overall signal control in the jurisdiction area.
Further, when a communication failure occurs in any one of the traffic signal controllers 4 among the traffic signal controllers 4, the control unit 22 controls the other traffic signal controllers 4 other than the traffic signal controller 4 in which the communication failure has occurred. Has a function of executing a maintenance process for maintaining system control with respect to.

Further, the control unit 22 has a function of registering the transmitted signal control command in the transmission-side database 46 (described later) stored in the storage unit 28.
Further, the control unit 22 issues a transmission request for requesting transmission of the signal control execution information generated during a predetermined period out of the signal control execution information stored in the execution information database 49 of the traffic signal controller 4. The traffic signal controller 4 also has a function of transmitting the signal control execution information for a predetermined period to the traffic signal controller 4.

  Further, when registering the signal control command transmitted by the central device 6 in the transmission side database 46 stored in the storage unit 28, the control unit 22 selects not to register some items such as staircase holding. It may have a function that can be set by setting. Further, when the signal control is intervened by a traffic-specific event or the like, the control unit 22 transmits to the central unit 6 and the traffic signal controller 4 that no signal control command is registered, and stores the signal control command in the storage unit 28. May not be registered in the transmission side database 46 stored in the storage unit 20 and the reception side database 42 stored in the storage unit 20.

The storage unit 28 stores the above-described transmission-side database 46 and the execution history database 51 in addition to various computer programs.
The transmission-side database 46 is a database for storing transmitted signal control commands transmitted by the own device 6, and a plurality of transmitted signal control commands are stored for each traffic signal controller 4. That is, the transmission-side database 46 constitutes higher-order accumulation data, which is a data group in which the transmitted signal control commands are accumulated for each traffic signal controller 4.
The execution history database 51 is a database for accumulating the signal control execution information given from the traffic signal controller 4, and the signal control execution information given from the traffic signal controller 4 in the past is stored for each traffic signal controller 4. Multiple files are stored.

The display unit 24 is configured by a display screen capable of displaying a road map of a jurisdiction area managed by the user, the positions of all the signal lights 2 and the traffic signal controllers 4 on the road map, traffic information, and the like. It is an output interface for outputting traffic conditions such as the above, the operation state of each traffic signal controller 4 and the like to the operator.
The operation unit 30 is an input interface such as a keyboard and a mouse. The operator can give necessary commands to the central device 6 through the operation unit 30.

[About the first embodiment]
[About control processing of signal light 2 by traffic signal controller 4]
FIG. 4 is a flowchart illustrating an example of control processing of the signal light 2 performed by the control unit 14 of the traffic signal controller 4 according to the first embodiment.
The control unit 14 first determines whether a communication failure has occurred with the central device 6 (step S1).

Here, the communication failure refers to a case where a signal control command from the central device 6 is not received for a predetermined time (for example, 10 minutes) due to occurrence of communication disconnection with the central device 6 or occurrence of a communication failure, or a predetermined number of times ( This means, for example, twice (two times) that an error has occurred in receiving the signal control command continuously.
The control unit 14 determines that a communication failure with the central device 6 has occurred when the signal control command from the central device 6 has not been received for a predetermined time or when an error has occurred in receiving the signal control command for a predetermined number of consecutive times. It is determined that it has occurred.

If it is determined in step S1 that a communication failure has not occurred with the central device 6, the control unit 14 determines whether a signal control command transmitted from the central device 6 has been received (step S3).
When determining that the signal control command has been received, the control unit 14 proceeds to step S4, and registers the received signal control command in the receiving-side database 42 (step S4).

FIG. 5 is a diagram illustrating an example of the signal control command 40 transmitted from the central device 6.
FIG. 6 is a diagram illustrating an example of the receiving-side database 42 stored in the storage unit 20 of the traffic signal controller 4.

FIG. 5 shows a part of the signal control command 40.
The “read command” among the items included in the signal control command 40 is a command for giving a signal controller having a learning function a timing to create or update a multi-stage operation time table. The control unit 14 can execute not only remote control by the central device 6 but also control using a timetable for multi-stage operation. For example, 10 to 30 patterns of the multistage operation timetable may be prepared in one signal controller. The control can be executed by switching these patterns depending on, for example, a time zone.
“Stairs holding” of the above items is a command related to holding the operating stairs for a long time.
The “status” among the above items refers to a signal presenting method and an execution state of an additional function.
“Sensitivity permission” among the above items is a command regarding whether or not to permit the traffic signal controller 4 to perform a sensitive operation.
“Sensitivity fluctuation width” among the above items is a command relating to the fluctuation width of the signal display time in the response operation in the traffic signal controller 4.
The “cycle length” in the above items refers to the time required for one cycle, and one cycle means that the signal display makes one cycle.

“Split” in the above items is a ratio of the length of time allocated to each announcement to the cycle length. Note that the present indication is a traffic right that is simultaneously given to a certain set of traffic flows or a time zone to which the traffic right is assigned at one intersection. Therefore, when the intersection is the intersection between the main road and the sub road, the intersection is set to each of the main road and the sub road.
The “offset reference time” in the above items is a time serving as a reference when counting the number of seconds of offset. The time obtained by adding the number of seconds of the offset and a multiple of the cycle length to the offset reference time is the rise of the first ladder.
In the above-mentioned item, "offset" refers to a point in time at which a signal is displayed in the system control or the regional control, for example, a deviation from a reference time common to the traffic signal group at a start time of a main road green light or the same display start between adjacent intersections. Point shift.
The “number of seconds in steps 1, 2,... N” is the number of seconds in each step.

As shown in FIG. 6, the receiving side database 42 has a column for registering an item corresponding to each item of the signal control command 40, and registers the content of the received signal control command 40. be able to.
In the receiving side database 42, each received signal control command 40 received in the past is registered in association with the reception date and time and the day type (day of the week).
In the receiving side database 42, for example, a plurality of signal control commands 40 received during a period of about one week in the past are accumulated.

As shown in FIG. 4, when the received signal control command 40 is registered in the receiving-side database 42 (step S4), the control unit 14 proceeds to step S5, executes normal processing, and returns to step S1.
If it is determined in step S3 that the signal control command 40 has not been received, the control unit 14 proceeds to step S5, executes normal processing, and returns to step S1.

FIG. 7 is a flowchart illustrating an example of the normal processing.
The control unit 14 that executes the normal process proceeds to step S11, and determines in step S12 and step S13 according to whether the determination result in step S3 in FIG. 4 has received the signal control command 40 from the central device 6. One is selected (step S11).
If the determination result in step S3 is that the signal control command 40 has been received from the central device 6, the control unit 14 proceeds to step S12 and performs signal control based on the received signal control command 40 (step S12). ), Finish the process.

  On the other hand, if the determination result in step S3 is that the signal control command 40 has not been received from the central device 6, the control unit 14 proceeds to step S13, and maintains the current signal control (step S13). Finish the process.

  Thus, in the normal processing, the control unit 14 performs signal control based on the latest signal control command 40 transmitted from the central device 6.

  In FIG. 4, if it is determined in step S1 that a communication failure has occurred with the central device 6, the control unit 14 proceeds to step S2, executes a non-reception process, and returns to step S1.

FIG. 8 is a flowchart illustrating an example of the non-receiving process.
The control unit 14 executing the non-receiving process proceeds to step S15, and selects the signal control command 40 corresponding to the current day type and time from the plurality of signal control commands 40 stored in the receiving database 42. (Step S15).

More specifically, the control unit 14 selects the signal control command 40 received at the date type and time corresponding to the current date type and time from the plurality of signal control commands 40 stored in the reception-side database 42. Select and browse.
Note that the day type refers to a day or a period in which a temporal change in traffic characteristics of the day shows the same pattern from the viewpoint of traffic control. There are three standard day types: weekday, Saturday, and holiday. Further, as the other day types, for example, the types may be classified according to a specific day of the week, or the types may be classified according to the weather.

  Here, the control unit 14 of the present embodiment receives, as a signal control command received at the day type and time corresponding to the current day type and time, the signal control instruction received at the same time on the same day one week before the current time or immediately before the same. The selected signal control command 40 is selected from the receiving side database 42 and referred to.

As shown in FIG. 8, the control unit 14 performs signal control based on the signal control command 40 referred to in step S15 (step S16), and ends the process.
Thus, in the non-receiving process, the control unit 14 performs signal control based on the signal control command 40 stored in the storage unit 20.

As described above, the control unit 14 switches the control of the signal light 2 to either the normal processing or the non-reception processing according to whether or not a communication failure has occurred with the central device 6.
In addition, the control unit 14 of the traffic signal controller 4 switches the processing so that when a communication failure occurs with the central device 6, the control unit 14 registers the communication failure in the reception side database 42 stored in the storage unit 20. The signal lamp 2 is controlled based on the signal control command 40 corresponding to the current day type and time among the signal control commands 40 of the own device 4.

[Transmission processing of signal control command by central device 6]
FIG. 9 is a flowchart illustrating an example of a transmission process of the signal control command 40 performed by the control unit 22 of the central device 6.

The control unit 22 first determines whether or not the traffic signal controller 4 in which communication failure has occurred with the own device 6 is included in the traffic signal controllers 4 in the jurisdiction area ( Step S20).
If it is determined in step S20 that the traffic signal controller 4 in which the communication failure has occurred with the own device 6 is not included in the jurisdiction area, the control unit 22 normally transmits the signal control command 40 ( Step S22), and return to step S20 again.

The normal transmission is a process of transmitting the latest signal control command 40 generated by the control unit 22 based on the current traffic information and the like to each traffic signal controller 4.
In this case, each traffic signal controller 4 maintains the normal processing (FIG. 7).

  If it is determined in step S20 that the traffic signal controller 4 in which the communication failure with the own device 6 is included in the jurisdiction area, the control unit 22 proceeds to step S23 and maintains the system control. (Step S23), and returns to step S20 again.

FIG. 10 is a flowchart illustrating an example of the maintenance process.
The control unit 22 that executes the maintenance processing first specifies the traffic signal controller 4 in which the communication failure has occurred, and performs the maintenance processing based on the position of the intersection where the traffic signal controller 4 in which the communication failure has occurred is installed. The traffic signal controller 4 to be executed is specified (step S24).
In the following description, the traffic signal controller 4 in which communication failure has occurred with the central device 6 is also referred to as a disconnection controller 4A.

  The control unit 22 of the present embodiment sets the traffic signal controller 4 installed at the intersection Ci that constitutes a sub area including the intersection where the disconnection controller 4A is installed, as an execution target of the maintenance processing. The sub-area indicates the minimum unit of the intersection group that always gives the same cycle length.

  The control unit 22 specifies the traffic signal controller 4 to be executed by the controller ID assigned to each traffic signal controller 4.

Next, the control unit 22 is a signal control command 40 transmitted from the transmission-side database 46 stored in the storage unit 28 to the cutting control device 4A, the signal control command corresponding to the current day type and time. 40 is selected and referred to (step S25).
More specifically, the control unit 22 is a signal control command 40 transmitted from the transmission-side database 46 to the cutting controller 4A, the signal transmitted at the date type and time corresponding to the current date type and time. The control command 40 is selected and referred to.

As described above, the control unit 22 registers the transmitted signal control command 40 transmitted by the own device 6 to each traffic signal controller 4 in the transmission-side database 46.
FIG. 11 is a diagram illustrating an example of the transmission-side database 46 stored in the storage unit 28 of the central device 6.

  As shown in FIG. 11, the transmission side database 46 is provided with a column for registering an item corresponding to each item of the signal control command 40, and the content of the transmitted signal control command 40 is stored in the traffic signal controller. 4 can be stored.

Each transmitted signal control command 40 transmitted in the past is registered in the transmission side database 46 in association with the transmission date and time and the day type (day of the week).
The transmission-side database 46 stores, for example, a plurality of signal control commands 40 transmitted during a period of about one week in the past.

  In the transmission side database 46, each transmitted signal control command 40 is registered in association with the controller ID. Thereby, the signal control command 40 transmitted by each traffic signal controller 4 in the jurisdiction area can be registered in the transmission side database 46 for each traffic signal controller 4.

  In FIG. 10, in step S25, the control unit 22 is associated with the controller ID of the cutting controller 4A from among the plurality of signal control commands 40 stored in the transmission-side database 46, and for one week from the present. The signal control command 40 transmitted at the same time or immediately before on the same previous day of the week is selected and referred to as the signal control command 40 transmitted on the day type and time corresponding to the current day type and time.

Next, the control unit 22 proceeds to step S26, and based on the referred signal control command 40 (the transmitted signal control command 40 transmitted to the cutting controller 4A), the signal control transmitted to the peripheral controller 4B. A command 40 is generated (Step S26).
The peripheral controller 4B refers to the traffic signal controllers 4 other than the cutting controller 4A among the traffic signal controllers 4 to be executed.

  The signal control command 40 for the peripheral controller 4B generated in step S26 is based on the premise that the cutting controller 4A is executing control in accordance with the signal control command 40 transmitted to the cutting controller 4A. Is generated as control contents that can realize system control by the entire cutting controller 4A and peripheral controller 4B.

Next, the control unit 22 proceeds to step S27, transmits the generated signal control command 40 to the peripheral controller 4B (step S27), and ends the processing.
The peripheral controllers 4B that have received the signal control command 40 transmitted in step S27 perform signal control based on the received signal control command 40, respectively.

As described above, the control unit 22 of the central device 6 uses the same selection policy as that used when each traffic signal controller 4 selects the signal control command 40 to be used in the non-reception processing, for the signal for the peripheral controller 4B. A signal control command 40 used to generate the control command 40 is selected.
Thereby, the control unit 22 of the central device 6 can grasp the signal control executed by the cutting controller 4A, and can appropriately control the peripheral controller 4B according to the control of the cutting controller 4A.

[Specific example of signal processing in the case where a disconnection controller exists in the first embodiment]
FIG. 12 is a diagram for explaining the operation of each traffic signal controller 4 and the central device 6 when the communication of one traffic signal controller 4 is cut off in the system of the first embodiment.

In FIG. 12, each intersection where the traffic signal controllers 4a, 4b, 4c, 4d, 4e, 4f, and 4g are installed is located in the section R in which the system control is performed.
Each intersection where the traffic signal controllers 4a, 4b, 4c, 4d and 4e are installed forms one sub-area A1, and each intersection where the traffic signal controllers 4f and 4g are installed is a sub-area. One sub-area A2 different from A1 is configured.

  Here, a case will be described in which the traffic signal controller 4b installed at the intersection in the sub-area A1 loses communication with the central device 6 for some reason, such as a change in the radio wave propagation path.

  When communication with the central device 6 is cut off in the traffic signal controller 4b, the traffic signal controller 4b cannot receive the signal control command 40 from the central device 6. Therefore, when a predetermined time has elapsed since the previous reception of the signal control command 40, the traffic signal controller 4b determines that the communication is poor, and executes the non-receiving process.

Here, it is assumed that the current date and time during which the traffic signal controller 4b determines that the communication is poor is Wednesday, August 28, 2018, 10:11:00 am.
As shown in FIG. 6, the receiving database 42 of the traffic signal controller 4b includes a signal control command 40 having a reception date and time of “August 21, 2018, Wednesday, 10:10:00 am”, It is assumed that a signal control command 40 whose reception date and time is “August 21, 2018, Wednesday, 10:12:00 am” is registered as the signal control command 40 received next to the signal control command 40. .

  As described above, the traffic signal controller 4b according to the present embodiment includes, among the signal control commands 40 stored in the reception-side database 42, a signal received at the same time or immediately before the same day of the week one week before the present. With reference to the control command 40, signal control is performed based on the referenced signal control command 40.

Therefore, the traffic signal controller 4b refers to the signal control command 40 stored in the receiving side database 42 and having the reception date and time “August 21, 2018, Wednesday, 10:10:00 am”, and Signal control is performed based on the signal control command 40.
Further, when the current date and time reaches Wednesday, August 28, 2018 at 10:12:00 am, the traffic signal controller 4b sets the reception date and time to “August 21, 2018, Wednesday, 10:12 am With reference to the signal control command 40 of "minute 00 seconds", signal control is performed based on the signal control command 40.
As described above, the traffic signal controller 4b refers to the signal control command 40 corresponding to the current day type and time according to the passage of time, and performs signal control based on the signal control command 40.

  On the other hand, when the central device 6 detects that the communication of the traffic signal controller 4b has been disconnected and that a communication failure has occurred with the traffic signal controller 4b, the central device 6 executes a maintenance process.

  The central device 6 of the present embodiment first specifies an execution target of the maintenance process. In FIG. 12, the intersection where the traffic signal controller 4b, which is the disconnection controller 4A, is installed is included in the sub-area A1. Therefore, the central device 6 specifies the traffic signal controllers 4a, 4b, 4c, 4d, 4e installed at the intersections included in the sub-area A1 as execution targets.

  Next, the central device 6 transmits the signal control command 40 stored in the transmission-side database 46 to the traffic signal controller 4b (disconnection controller 4A) at the same time on the same day of the week one week before or immediately before the current time. The signal control command 40 is referred to. Then, the central device 6 generates a signal control command 40 to be transmitted to the traffic signal controllers 4a, 4c, 4d, 4e (peripheral controller 4B) based on the referred signal control command 40.

Here, similarly to the above, it is assumed that the current date and time is Wednesday, August 28, 2018, 10:11:00 AM.
In addition, as shown in FIG. 11, the transmission date and time of the transmission-side database 46 as the signal control command 40 associated with the controller ID of the traffic signal controller 4b is “August 21, 2018, Wednesday, A signal control command 40 of “10:10:00” and a signal control command 40 transmitted next to the signal control command 40 with a transmission date and time of “August 21, 2018, Wednesday, 10:12:00 am Is registered.

  Accordingly, in this case, the central device 6 is associated with the controller ID of the traffic signal controller 4b stored in the transmitter database 46, and the transmission date and time is “August 21, 2018, Wednesday, 10 am 10:00 ”, the signal control command 40 is referred to. Then, based on the referred signal control command 40 (the signal control command 40 transmitted to the traffic signal controller 4b), the central device 6 controls the signal transmitted to the traffic signal controllers 4a, 4c, 4d, 4e. A command 40 is generated.

  The central device 6 generates the signal control command 40 generated for each of the traffic signal controllers 4a, 4c, 4d, 4e based on the signal control command 40 which has been transmitted to the traffic signal controller 4b, to the traffic signal controllers 4a, 4c, 4d. , 4e.

The traffic signal controllers 4a, 4c, 4d, and 4e, which are the peripheral controllers 4B whose communication has not been disconnected, perform signal control based on the received signal control command 40.
Further, when the current date and time reaches Wednesday, August 28, 2018 at 10:12:00 am, the central device 6 is associated with the controller ID of the traffic signal controller 4b and the transmission date and time are set. With reference to the signal control command 40 of “August 21, 2018, Wednesday, 10:12:00 am”, signal control is performed based on the signal control command 40.
As described above, the central device 6 refers to the signal control command 40 of the cutting controller 4A corresponding to the current day type and time according to the passage of time, and based on the signal control command 40, the peripheral controller 4B A signal control command 40 is generated and transmitted to the peripheral controller 4B.

  As described above, in the present embodiment, the traffic signal controller 4b, which is the cutting controller 4A, performs signal control based on the signal control command 40 received in the past, whereas the traffic signal controller 4B, which is the peripheral controller 4B, performs signal control. The controllers 4a, 4c, 4d, and 4e perform signal control based on the signal control command 40 generated based on the signal control command 40 transmitted to the traffic signal controller 4b in the past.

  The traffic signal controllers 4f and 4g installed at the intersection of the sub-area A2 maintain the normal processing. In addition, the central device 6 maintains normal transmission to the traffic signal controllers 4f and 4g.

  According to the system 1 having the above configuration, even if the traffic signal controller 4b in which the communication failure occurs is included in the plurality of traffic signal controllers 4, the traffic signal controller 4b in which the communication failure occurs is included in the traffic signal controller 4b. Since the signal lamp 2 is controlled based on the signal control command 40 corresponding to the current time in the reception side database 42 of the traffic signal controller 4b, the signal control executed in the past with the same day type and time as the current time Execute Thus, the control executed in the past traffic situation similar to the current traffic situation can be executed, and the signal control can be appropriately performed.

  In addition, the central device 6 of the present embodiment can obtain the signal control command 40 currently used by the cutting controller 4A. Furthermore, since the signal control command 40 of the peripheral controller 4B is generated based on the signal control command 40 currently used by the cutting controller 4A, the signal control of the peripheral controller 4B is changed to the signal control of the cutting controller 4A. In addition, it can be performed more appropriately. As a result, system control between the cutting controller 4A and the peripheral controller 4B can be more appropriately maintained.

  Further, in the present embodiment, the peripheral controller 4B is centrally controlled by the signal control command 40 from the central device 6, so that, for example, even when the communication failure of the disconnecting controller 4A is over a long period of time, the peripheral controller 4B can be flexibly handled. And proper signal control can be maintained for a long period of time.

Furthermore, the central device 6 of the present embodiment sets the traffic signal controller 4 installed at the intersection Ci, which constitutes a sub area including the intersection where the cutting controller 4A is installed, as an execution target of the maintenance processing.
That is, since each intersection Ci where the cutting controller 4A and the peripheral controller 4B are installed forms one sub-area A1 in the section of the system control, the traffic signal controller that executes the signal control with the same cycle length 4 can be appropriately signal-controlled.

  In the present embodiment, the traffic signal controller 4b, which is the disconnection controller 4A, is based on the signal control command 40 selected from the signal control commands 40 registered in the receiving database 42 of the own device 4. , Cycle control, split control, offset control, and terminal-sensitive control.

  On the other hand, the traffic signal controllers 4a, 4c, 4d, and 4e, which are the peripheral controllers 4B, may execute the cycle control and the offset control based on the signal control command 40 transmitted from the central device 6, and perform the split control. The control and the terminal-sensitive control may be executed based on a measurement result from the roadside sensor 8 connected to each traffic signal controller 4 or based on a signal control command 40 transmitted from the central device 6. May be performed.

[Regarding execution history]
The system 1 has a function of accumulating, as a history, the content of signal control actually executed by each traffic signal controller 4.
The history accumulation function is performed when each traffic signal controller 4 transmits signal control execution information to the central device 6 and the central device 6 registers the information in the execution history database 51.
Therefore, when a communication failure occurs between the traffic signal controller 4 and the central device 6, information in the execution history database 51 is partially lost.
The system 1 has a function of performing a restoration process for restoring information in the lost execution history database 51.

  FIG. 13 is a sequence diagram illustrating an example of the restoration process. Although FIG. 13 focuses on the processing between one traffic signal controller 4 and the central device 6, the central device 6 executes the same processing as each traffic signal controller 4.

  First, in FIG. 13, the traffic signal controller 4 generates signal control execution information indicating the content of the control of the signal lamp 2 executed by the own device 4 and registers the signal control execution information in the execution information database 49 of the storage unit 20 of the own device 4. (Step S30). Next, the traffic signal controller 4 transmits the generated signal control execution information to the central device 6 (Step S31).

FIG. 14 is a diagram illustrating an example of the signal control execution information transmitted by the traffic signal controller 4.
FIG. 14 shows a part of the signal control execution information 50.
The “transmission date and time” of the items included in the signal control execution information 50 indicates the transmission start date and time (year, month, day, hour, minute, and second) and the end date and time (year, month, day, hour, minute, and second) of the signal control execution information. “Cycle start time” is the start time of the current cycle.
The “control execution type” among the above items is information indicating a status used in a remote operation, a manual operation, an independent operation, a security operation, a flash operation, and the like, and includes information indicating a history operation.
The “sensitive execution type” among the above items is information indicating FAST control, recall control, gap sensitive control, and the like in which the terminal device operates based on the sensitive permission signal.
The “split variation value” in the above items is a number of seconds that is extended or shortened with respect to a reference number of seconds when the sensitive control is executed based on the above-described sensitive permission signal.

“Execution offset” in the above items indicates the value of the offset actually executed.
The "number of seconds in steps 1, 2,... N" is the number of seconds of each step actually executed.
The “scheduled cycle length” in the above items indicates the cycle length that the traffic signal controller is trying to execute.
The "automatic generation result" among the above items is calculated by a function of automatically generating a cycle and a split while calculating a traffic volume and an occupation time per unit time for each vehicle sensor based on information from the vehicle sensor. This is the result.
“Sensor information” among the above items indicates a measurement result from the roadside sensor 8.
The “operation state information” among the above items indicates information on the state of remote operation, lamp color abnormality, clock abnormality, and the like.
The “speed measurement information” among the above items is information indicating the speed of the vehicle 5 measured by the roadside sensor 8.

The traffic signal controller 4 generates the signal control execution information 50, registers the generated signal control execution information 50 in the execution information database 49 of the storage unit 20 of the own device 4, and stores the generated signal control execution information 50. Transmit to central device 6.
The central device 6 that has received the signal control execution information 50 registers the received signal control execution information 50 in the execution history database 51 stored in the storage unit 28 of the own device 6 (Step S32).

In the execution history database 51 of the central device 6, signal control execution information 50 is accumulated in association with each controller ID of the traffic signal controller 4 in the jurisdiction area. In the execution history database 51, signal control execution information 50 of each traffic signal controller 4 is continuously registered.
Therefore, a plurality of pieces of signal control execution information 50 are registered in the execution history database 51 so that the signal control execution information 50 is continued over time without loss.
The execution history database 51 is used to manage the history of control actually executed by the traffic signal controller 4.

  When registering the signal control execution information 50 in the execution history database 51, the central device 6 sets the content of “transmission date and time” in the item of the signal control execution information 50 to the reception date and time when the signal control execution information 50 was received. Change and register.

  As shown in FIG. 13, the traffic signal controller 4 repeats the generation, registration, and transmission of the signal control execution information 50 as needed (steps S33 and S34), and accordingly, the central device 6 receives the signal control execution information 50 50 is registered in the execution history database 51 as needed (step S35).

Next, after step S35, it is assumed that a communication failure occurs between the traffic signal controller 4 and the central device 6 (step S36), and thereafter, the communication is restored (step S38).
In this case, the traffic signal controller 4 continues to generate the signal control execution information 50 and register the signal control execution information 50 in the execution information database 49 during the disconnection period from the occurrence of the communication failure to the recovery. (Step S37).

However, the traffic signal controller 4 cannot transmit the signal control execution information 50 because a communication failure has occurred with the central device 6.
For this reason, the central device 6 cannot receive the signal control execution information 50 generated during the disconnection period, and the signal history of the signal control execution information 50 during the disconnection period is lost in the execution history database 51.

If the signal control execution information 50 is lost in the execution history database 51 and the continuity of the execution history database 51 with time is impaired, the central device 6 determines the period during which the signal control execution information 50 is lost (predetermined). A transmission request for requesting transmission of the signal control execution information 50 during the period is transmitted to the traffic signal controller 4 (step S39). When the central device 6 determines that a communication failure has occurred and the continuity over time of the execution history database 51 has been impaired, the central device 6 transmits a transmission request, but the continuity over time of the execution history database 51 is impaired. The transmission of the transmission request may be performed by displaying the fact on the display unit 24 and outputting it to the operator, and accepting the input of the operator by the operation unit 30.
Note that the transmission request includes information indicating a period (disconnection period) during which the execution history database 51 of the central device 6 has a defect.

  The traffic signal controller 4 that has received the transmission request generates loss compensation information (step S40). The defect compensation information is information including the signal control execution information 50 generated during the cutting period among the plurality of signal control execution information 50 registered in the execution information database 49.

FIG. 15 is a diagram illustrating an example of loss compensation information transmitted by the traffic signal controller 4.
FIG. 15 shows a part of the defect compensation information 52.
The “transmission date and time” of the items included in the loss compensation information 52 indicates the transmission start date and time (year, month, day, hour, minute, and second) and the end date and time (year, month, day, hour, minute, and second) of the loss compensation information 52.
The defect compensation information 52 includes the same items as the signal control execution information 50.
As another item, “repair date and time” is the date and time (year, month, day, hour, minute, and second) when the loss compensation information 52 is given to the central device 6 and registered in the execution history database 51 to repair the loss. The information is written by the central device 6 that has received the defect compensation information 52.
“Probe information” is probe information of the vehicle 5 collected by the roadside sensor 8 connected to the traffic signal controller 4. The traffic signal controller 4 accumulates probe information from the roadside sensor 8 during the disconnection period. The traffic signal controller 4 transmits the probe information accumulated during the disconnection period while including the probe information in the defect compensation information 52.

When the traffic signal controller 4 generates the loss compensation information 52, it transmits it to the central device 6 (step S41).
The central device 6 that has received the loss compensation information 52 restores the execution history database 51 using the loss compensation information 52. At this time, the central device 6 changes the content of “transmission date and time”, which is an item of the loss compensation information 52, to the reception date and time at which the loss compensation information 52 was received and registers it.
Further, the central device 6 writes the date and time when the execution history database 51 was repaired based on the loss compensation information 52 into “repair date and time”.

  Note that the probe information included in the defect compensation information 52 is used by the central device 6 to generate traffic information.

As described above, in the present embodiment, each traffic signal controller 4 generates the signal control execution information 50 and stores the signal control execution information 50 in the execution information database 49 of the storage unit 20 of the own device 4.
Further, the central device 6 issues a transmission request for requesting transmission of the signal control execution information 50 of the disconnection period (predetermined period) of the plurality of signal control execution information 50 registered in the execution information database 49, to the traffic signal controller. 4 and the traffic signal controller 4 can transmit the signal control execution information 50 for a predetermined period as loss compensation information 52.
As a result, the central device can acquire the execution information of the traffic signal controller during the communication failure as the execution history, and can repair the missing portion of the execution history database 51.

[About the second embodiment]
FIG. 16 is a flowchart illustrating an example of a maintenance process performed by the central device 6 of the system according to the second embodiment.
This embodiment is different from the first embodiment in that the maintenance process executed by the central device 6 is a process of stopping the transmission of the signal control command 40 to the peripheral controller 4B.

As in the first embodiment, (the control unit 22 of) the central device 6 of the present embodiment first specifies the disconnection controller 4A in which the communication failure has occurred, and the traffic signal controller to be subjected to the maintenance processing. 4 (step S24).
Also in the present embodiment, the central device 6 sets the traffic signal controller 4 installed at the intersection Ci that constitutes a sub-area including the intersection where the cutting controller 4A is installed, as an execution target of the maintenance processing.

  Next, the central device 6 stops transmitting the signal control command 40 to each of the traffic signal controllers 4 installed at the intersection Ci forming the sub-area including the cutting controller 4A (Step S28), and ends the processing.

At this time, since the peripheral controller 4B included in the sub-area determines that a communication failure has occurred with the central device 6, the peripheral controller 4B executes the non-receiving process similarly to the disconnect controller 4A.
In the non-receiving process, the traffic signal controller 4 refers to the signal control command 40 corresponding to the current day type and time, and performs signal control based on the signal control command 40.

At this time, the cutting controller 4A and the peripheral controller 4B perform signal control based on the signal control command 40 received at the same timing in the past.
Therefore, the cutting controller 4A and the peripheral controller 4B reproduce the signal control executed at the same timing in the past, and can maintain the system control.

[Specific example of signal processing in the case where a disconnection controller exists in the second embodiment]
FIG. 17 is a diagram for explaining the operation of each traffic signal controller 4 and the central device 6 when the communication of one traffic signal controller 4 is disconnected in the system of the second embodiment.

FIG. 17 shows the traffic signal controllers 4a, 4b, 4c, 4d, 4e, 4f, 4g installed at the respective intersections located in the section R where the system control is performed, as in FIG.
Each intersection where the traffic signal controllers 4a, 4b, 4c, 4d and 4e are installed forms one sub-area A1, and each intersection where the traffic signal controllers 4f and 4g are installed is a sub-area. One sub-area A2 different from A1 is configured.

  Here, a case will be described in which the traffic signal controller 4b installed at the intersection in the sub-area A1 loses communication with the central device 6 for some reason, such as a change in the radio wave propagation path.

As in the case of FIG. 12, it is assumed that the current date and time during which the traffic signal controller 4b determines that the communication is poor are Wednesday, August 28, 2018, 10:11:00 AM.
As shown in FIG. 6, the receiving date and time of the traffic signal controllers 4a, 4b, 4c, 4d, and 4e are "August 21, 2018, Wednesday, 10:10 am Second control signal 40 and a signal control command 40 received next to the signal control command 40 with a reception date and time of "August 21, 2018, Wednesday, 10:12:00 am". Is registered.

  In this case, the traffic signal controller 4b, which is the disconnection controller 4A, executes the non-reception processing, and the reception date and time stored in the reception side database 42 is “August 21, 2018, Wednesday, 10:10 am With reference to the signal control command 40 of "minute 00 seconds", signal control is performed based on the signal control command 40.

At this time, when the central device 6 determines that a communication failure has occurred with the traffic signal controller 4b, the central device 6 issues a signal control command to the traffic signal controllers 4a, 4c, 4d, and 4e, which are the peripheral controllers 4B. 40 transmission is stopped.
Therefore, the traffic signal controllers 4a, 4c, 4d, and 4e perform the non-reception processing similarly to the traffic signal controller 4b, and the reception date and time stored in the respective reception side databases 42 is “August 2018”. The signal control is performed on the basis of the signal control command 40 with reference to the signal control command 40 of “21:10, Wednesday, 10:10:00 am”.

  In this case, the traffic signal controllers 4a, 4c, 4d, and 4e, which are the peripheral controllers 4B, stop transmitting the signal control command 40, and thus, the traffic signal controllers 4a, which are the disconnection controllers 4A, as well as the central traffic signal controller 4b. It determines that a communication failure has occurred with the device 6, and executes signal control based on the signal control command 40 corresponding to the current day type and time. As a result, signal control executed in the past at the same day type and time at the current intersection can be reproduced, and system control can be maintained.

  In the second embodiment, when the execution target is specified, the central device 6 stops transmitting the signal control command 40 to the peripheral controller 4B in step S28, but the central device 6 performs the signal control command. An operator for outputting a display indicating the traffic signal controller 4 corresponding to the peripheral controller 4B at which transmission of the signal 40 should be stopped to the display unit 24, and further stopping transmission of the signal control command 40 to the peripheral controller 4B. The transmission of the signal control command 40 to the peripheral controller 4B may be stopped by receiving the input by the operation unit 30.

[Management of time information by start time of each step]
As shown in FIG. 14, the format of the signal control execution information 50 includes “cycle start time” and “scheduled cycle length” for a cycle, but “seconds” for steps 1, 2,. The number is to be sent.
In this case, the value of the number of seconds described in each of the steps 1, 2,... N is a value determined by the traffic signal controller 4 by a rounding process such as rounding. Therefore, the total value of the number of seconds of all steps included in the cycle may not match the number of seconds of the cycle length, and the central device 6 may not be able to obtain accurate signal control execution information 50.

Therefore, the format of the signal control execution information 50 may employ any of the following patterns instead of the “number of seconds” in steps 1, 2,. As a result, it is possible to reduce the accumulated error caused by the fraction processing.
・ Pattern 1
"Start time" of each step 1, 2,... N
・ Pattern 2
"Start time" of step 1 and "cumulative number of seconds until start" of each step from "start time" of step 1

・ Pattern 3
“Start time” of step 1 and “cumulative number of seconds from end” to “end” of each step
Here, in the “start time”, hours, minutes, and seconds (the number of seconds is in units of 1 second or 0.1 second) are described, and “cumulative seconds until start” and “cumulative seconds until end” are set. Indicates a second numerical value such as a one-second unit or a 0.1-second unit.

  For example, assuming that the cycle start time is “10:00:00”, the time length of the first step is “40 seconds”, and the time length of the second step is “5 seconds”. The signal control execution information 50 based on 3 is as follows.

In the case of pattern 2 (the cumulative number of seconds from the start time of step 1 to the start of each step)
Cycle start time: 10:00:00
First step start: 0 seconds Second step start: 40 seconds Third step start: 45 seconds

In the case of pattern 3 (the cumulative number of seconds from the start time of step 1 to the end of each step)
Cycle start time: 10:00:00
End of the first step: 40 seconds End of the second step: 45 seconds

It is to be noted that not only the signal control execution information 50 but also the format of the signal control command 40 shown in FIG. It may be.
When any of the above three patterns is adopted, the absolute time including “year, month, day” as the start time of the cycle or each step, the cumulative number of seconds until the start of each step, or the cumulative number of seconds until the start of each step, It is preferable to use time. In this way, even when the same step continues for a long period of time, the start time of each step can be accurately identified.

The traffic signal controller 4 transmits, as an operation state every one second, the presence / absence of a recall, light out, operation of a generator for power failure (if a generator is provided), door opening / closing state (with a door opening / closing detection function) and the like. There are cases.
These information transmissions are executed in units of one second when the communication with the traffic control center is maintained, and at least one of these states (events) is transmitted in absolute time (year / month / day / hour / minute / second). It may be transmitted in a format.

In this way, the central device 6 can grasp the start and end of the event (for example, the start date and time and the minute and the end of the event and the end date and time and minute and second).
In particular, when communication between the traffic control center and the traffic signal controller 4 is interrupted, the time of event recovery during line disconnection can be accurately grasped at a later date.

[Others]
It should be noted that the embodiments disclosed this time are illustrative in all aspects and not restrictive.
For example, in the first embodiment and the second embodiment, the central device 6 maintains the traffic signal controller 4 installed at the intersection Ci that constitutes a sub-area including the intersection where the cutting controller 4A is installed, in the maintenance processing. Although the case where it is set as an execution target is illustrated, the traffic signal controller 4 of the intersection Ci located in a predetermined range based on the intersection Ci where the cutting control device 4A is installed can be set as the execution target.

That is, each intersection Ci where the peripheral controller 4B is installed is located within a predetermined range based on the intersection Ci where the cutting controller 4A is installed in the section of the system control.
Thereby, the traffic signal controller 4 adjacent to the cutting controller 4A in the section of the system control can be set as the peripheral controller 4B.

Further, the predetermined range that defines the intersection Ci at which the peripheral controller 4B is installed is a range from the intersection Ci at which the cutting controller 4A is installed to the intersection Ci located before the important intersection adjacent to the intersection Ci. There may be.
The important intersection refers to an intersection serving as a reference for determining a signal control parameter of a related intersection in system control or surface control. Where traffic demand is high, the intersection is a bottleneck in traffic capacity.

FIG. 18 is a diagram for explaining another example when specifying an execution target. FIG. 18 illustrates a case where an important intersection is included in the section R in which the system control is performed.
In FIG. 18, it is assumed that the intersection Ci where the traffic signal controllers 4h and 4n are installed is an important intersection.
The intersection where the traffic signal controllers 4h, 4i, 4j and 4k are installed forms one sub-area A3, and the intersection where the traffic signal controllers 4l and 4m are installed is the sub-area A3. And another sub-area A4.

  In the example of FIG. 18, the central device 6 is a traffic signal controller installed in a range from an intersection Ci where the cutting controller 4A is installed to an intersection Ci located just before an important intersection adjacent to the intersection Ci. 4 is to be executed.

  Here, it is assumed that a communication failure occurs with the central device 6 in the traffic signal controller 4k installed at the intersection in the sub area A3.

In this case, the central device 6 executes the traffic signal controllers 4i, 4j, 4k, 41, and 4m located in the range between the traffic signal controllers 4h and 4n, which are important intersections, regardless of the sub-areas A3 and A4. set to target.
Also in this configuration, system control can be maintained and signal control can be appropriately performed.

  Further, in each of the above embodiments, the control unit 14 of the traffic signal controller 4 searches the reception side database 42 for the signal control command 40 received at the same time on the same day of the week or one week before the current time or immediately before. , The case of reference is illustrated. In other words, the case where the unit for determining whether or not the day type corresponds to the day unit has been described as an example. However, the day type corresponding to the current day type is determined in three units of weekdays, Saturdays, and holidays. You may.

  Further, in each of the above-described embodiments, the case where each traffic signal controller 4 and the central device 6 perform wireless communication with each other by the mobile communication system has been exemplified, but the communication between each traffic signal controller 4 and the central device 6 is performed. Is not limited to wireless communication, but may be communication via a wired LAN or a wired line such as a wired telephone line.

  The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Traffic signal control system 2 Signal light 4 Traffic signal controller 4a, 4b, 4c, 4d, 4e, 4f, 4g Traffic signal controller 4h, 4i, 4j, 4k, 41, 4m, 4n Traffic signal controller 4A Disconnection control Machine 4B Peripheral controller 5 Vehicle 6 Central unit 8 Roadside sensor 10 Roadside communication device 14 Control unit 16 Lighting drive unit 18 Communication unit 20 Storage unit 22 Control unit 24 Display unit 26 Communication unit 28 Storage unit 30 Operation unit 40 Signal control command 42 Reception side database 46 Transmission side database 49 Execution information database 50 Signal control execution information 51 Execution history database 52 Compensation information A1 sub area A2 sub area A3 sub area A4 sub area

Claims (11)

A plurality of traffic signal controllers installed at intersections included in the system control section,
A central device that notifies a signal control command for system control to the plurality of traffic signal controllers, and a traffic signal control system comprising:
The central unit comprises:
An upper control unit that generates the signal control command for each of the plurality of traffic signal controllers,
An upper communication unit that transmits the generated signal control command to each of the plurality of traffic signal controllers,
The plurality of traffic signal controllers,
A lower communication unit that receives the signal control command of the own device,
A lower control unit that controls the signal lamp based on the received signal control command;
A lower-level storage unit that stores lower-level accumulated data, which is a data group in which the received signal control command of the own device has been stored,
The lower-side control unit includes:
When a communication failure occurs with the central device, the signal light based on a signal control command corresponding to the current day type and time among the signal control commands of the own device included in the lower-order accumulated data. Traffic signal control system that controls the vessel. The central unit comprises:
The traffic signal control system according to claim 1, further comprising an upper storage unit that stores upper stored data, which is a data group in which the transmitted signal control command is stored for each of the plurality of traffic signal controllers. The upper control unit,
When the following cutting controller is detected, the signal control command of the cutting controller corresponding to the current day type and time is extracted from the signal control commands of the cutting controller included in the higher-order accumulated data. And
The traffic signal control system according to claim 2, wherein the signal control command of the following peripheral controller is generated based on the extracted signal control command of the cutting control device.
Disconnect controller: Traffic signal controller in which communication failure has occurred with the central device Peripheral controller: Traffic signal controller included in the same system control section as the disconnect controller and communicating with the central device The upper control unit,
The traffic signal control system according to claim 1 or 2, wherein the transmission of the signal control command to the following peripheral controller is stopped when the following disconnection controller is detected.
Disconnect controller: Traffic signal controller in which communication failure has occurred with the central device Peripheral controller: Traffic signal controller included in the same system control section as the disconnect controller and communicating with the central device The traffic signal control system according to claim 3, wherein each intersection where the disconnection controller and the peripheral controller are installed forms one sub-area in the section. 5. The traffic signal control system according to claim 3, wherein each intersection where the peripheral controller is installed is located within a predetermined range based on an intersection where the cutting controller is installed in the section. 6. . The traffic signal control system according to claim 6, wherein the predetermined range is a range from an intersection where the cutting control device is installed to an intersection located before an important intersection adjacent to the intersection. The plurality of traffic signal controllers,
While generating the execution information indicating the control of the signal light device executed by the own machine and accumulating the execution information in the lower storage unit,
The central unit comprises:
A transmission request for requesting transmission of execution information generated during a predetermined period of the execution information stored in the lower storage unit is transmitted to at least one of the plurality of traffic signal controllers. The traffic signal control system according to any one of claims 1 to 7, wherein execution information of the predetermined period is transmitted to the one traffic signal controller. Traffic signal control performed by a plurality of traffic signal controllers installed at intersections included in the section of system control, and a central device that notifies the plurality of traffic signal controllers of a signal control command for system control. The method
The central device generates the signal control command for each of the plurality of traffic signal controllers,
The central device transmits the generated signal control command to each of the plurality of traffic signal controllers,
The traffic signal controller, receiving the signal control command of its own,
The traffic signal controller controls a signal light based on the received signal control command,
The traffic signal controller has a step of storing lower-order accumulated data, which is a data group in which the received signal control command of the own device has been accumulated,
The traffic signal controller controls the signal lamp based on the received signal control command, when a communication failure occurs with the central device, the traffic light controller of its own device included in the lower-side accumulated data A traffic signal control method for controlling the signal lamp based on a signal control command corresponding to a current day type and time among the signal control commands. A traffic signal controller installed at an intersection included in the section of the system control,
A lower communication unit that receives a signal control command for system control,
A lower control unit that controls the signal lamp based on the received signal control command;
A lower-level storage unit that stores lower-level stored data, which is a data group in which the received signal control commands are stored,
The lower-side control unit includes:
When a communication failure occurs with the central device that notifies the signal control command, based on the signal control command corresponding to the current day type and time among the signal control commands included in the lower-order accumulated data. A traffic signal controller for controlling the signal light. A computer program for causing a computer to execute control of a signal light by a traffic signal controller installed at an intersection included in a section of system control,
On the computer,
Receiving a signal control command for system control;
Controlling the signal lamp based on the received signal control command;
Storing the lower-order accumulated data, which is a data group in which the received signal control commands are accumulated, and
Controlling the signal lamp based on the received signal control command,
When a communication failure occurs with the central device that notifies the signal control command, based on the signal control command corresponding to the current day type and time among the signal control commands included in the lower-order accumulated data. And a computer program for controlling the signal lamp.

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